For motor vehicles with an automatic transmission, a driver can usually engage a park stage in the automatic transmission after the motor vehicle has been parked and/or pull an electronic parking brake in order to prevent the motor vehicle from rolling. For selection of the park stage, the driver can usually actuate a selector lever, with the selector lever actuation being detected via a selector lever control instrument and then being conveyed to a transmission control instrument, which ultimately brings about engagement of the park stage. However, communication errors can ensue, so that, for example, the park stage of the automatic transmission can no longer be engaged and/or the electronic park stage can no longer be pulled. Beyond this, when communication errors of this kind occur, it can also happen that a driver receives no warning relating to the existing malfunction in regard to the automatic transmission and/or the electronic parking brake. In the event of an error, a safe parking of the motor vehicle can thereby be made difficult or, under certain circumstances, even made impossible, without the driver being alerted to this fact.
DE 10 2010 007 899 B4 shows a method for operating a motor vehicle. In the case that the motor vehicle has been braked all the way to a stop by means of an automatic longitudinal guidance system, an electronic parking brake of the motor vehicle is activated. In the case that a malfunction is thereby detected on the electronic parking brake, either a park stage of an automatic transmission of the motor vehicle is engaged automatically or an alert is output by means of a display device of the motor vehicle to engage manually the park stage of the automatic transmission.
DE 10 2008 018 470 A1 shows an apparatus for actuating a parking lock of a motor vehicle. By means of two mutually independent control units, an actuation of the parking lock can occur. For this purpose, a separate actuating means for actuation of the parking lock is associated with each of the control units. The two control units can communicate with each other via a bus connection of the motor vehicle. Once a faulty operation of one of the two control units is detected, a corresponding fault message can be output to a driver of the motor vehicle.
EP 2 361 812 B1 shows a method for operating a utility vehicle. In the case that, during an automatic actuation of an emergency brake of the utility vehicle in the course of a test cycle, it is detected that the utility vehicle does not stand still, an error signal is transmitted to a control instrument. In consequence thereof, the control instrument engages an operating brake of the utility vehicle. Beyond this, it can be provided that a signal pertaining to the error signal is output to a driver of the utility vehicle.